Carrier-based PWM strategies for the comprehensive capacitor voltage balance of multilevel multileg diode-clamped converters

摘要

This paper presents four carrier-based PWM\udstrategies for diode-clamped converters of any number of levels and any number of legs (phases). These carrier-based PWM\udstrategies guarantee the dc-link capacitor voltage balance in\udevery switching cycle without the need of additional hardware\udand with low dc-link capacitance values for any modulation\udindex and load, provided that the sum of leg currents equals\udzero. The performance of the presented carrier-based PWM\udstrategies, in terms of dc-link capacitor voltage balance and total\udharmonic distortion in the output line-to-line voltages, is\udevaluated through simulation, showing a tradeoff between the\udsimplicity of the carrier-based PWM implementation and its\udtotal harmonic distortion performance.